i dont think it matters. i put my in the front obly because I wanted it to bring out the color in my zoo's and my frogspawn. now, if you have some nice zoos or a bright coral you wanna bring out in the back, you could put it there but i would just put it in the front to make sure everyone gets light.i wish i could get a decent shot of my candy cane in the top right, the blue in the centers are now neon teal. its nuts. but its really your preference. post some pics when you get em in! itl look sick trust me.
p.s my clown looks way prettier. his white bars stand out so much more and have a sort of blue/silver tink to them.